Online platforms frequently include various social cues next to items to assist users with their choice, e.g. the number and the average value of previous user ratings. Numerous studies have shown that users actively leverage such information when making purchasing or consumption decisions [1]}, [2]}, [3]}, [4]}, [5]}, [6]}, [7]}, [8]}, [9]}, [10]}, [11]}.
[1]} found that artificially inflating download counts for some of the products on a software download service led to those products receiving more subsequent downloads than their unaltered counterparts.
Similarly, [5]} report that Chrome Web Store users rarely click on items displayed with a low download count.
[4]} noted
that users exposed to the average rating also rated movies closer to that average.
Analogously, [3]} found that participants reported higher purchasing intent for high-rated items over low-rated items and that this effect arose from an improved perception of quality and value.
Both studies also reported that the strength of the effect was positively correlated with the item's number of ratings, consistent with earlier works associating larger group size with stronger herding [16]}, [17]}, [10]}.
Altogether, these observations suggest that users incorporate the experience of others into their own judgements and the strength of this effect is correlated with the size of the group.
